Abiraterone, an anti-cancer medication, is primarily used to treat prostate cancer. While it's not specifically designed to shrink tumors, it can help slow down the growth of cancer cells and alleviate symptoms associated with advanced prostate cancer. It works by inhibiting the production of androgens, which are hormones that can fuel the growth of prostate cancer cells. Abiraterone is often prescribed in combination with other treatments to effectively manage the disease. However, its effectiveness in shrinking tumors may vary from person to person, and it's essential to consult with a healthcare professional for personalized treatment recommendations and expectations.